enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Möbius–Hückel concept - Wikipedia

    en.wikipedia.org/wiki/Möbius–Hückel_concept

    Möbius (left) and Hückel (right) orbital arrays. The two orbital arrays in Figure 3 are just examples and do not correspond to real systems. In inspecting the Möbius one on the left, plus–minus overlaps are seen between orbital pairs 2-3, 3-4, 4-5, 5-6, and 6-1, corresponding to an odd number (5), as required by a Möbius system.

  3. Hückel method - Wikipedia

    en.wikipedia.org/wiki/Hückel_method

    The Hückel method or Hückel molecular orbital theory, proposed by Erich Hückel in 1930, is a simple method for calculating molecular orbitals as linear combinations of atomic orbitals. The theory predicts the molecular orbitals for π-electrons in π-delocalized molecules , such as ethylene , benzene , butadiene , and pyridine .

  4. Möbius aromaticity - Wikipedia

    en.wikipedia.org/wiki/Möbius_aromaticity

    In organic chemistry, Möbius aromaticity is a special type of aromaticity believed to exist in a number of organic molecules. [ 1 ] [ 2 ] In terms of molecular orbital theory these compounds have in common a monocyclic array of molecular orbitals in which there is an odd number of out-of-phase overlaps, the opposite pattern compared to the ...

  5. Erich Hückel - Wikipedia

    en.wikipedia.org/wiki/Erich_Hückel

    He is mainly known for the Debye–Hückel theory of electrolytic solutions and the Hückel method of approximate molecular orbital (MO) calculations on π electron systems. Hückel was born in the Charlottenburg suburb of Berlin. He studied physics and mathematics from 1914 to 1921 at the University of Göttingen.

  6. Hückel's rule - Wikipedia

    en.wikipedia.org/wiki/Hückel's_rule

    Benzene, the most widely recognized aromatic compound with six delocalized π-electrons (4n + 2, for n = 1).. In organic chemistry, Hückel's rule predicts that a planar ring molecule will have aromatic properties if it has 4n + 2 π-electrons, where n is a non-negative integer.

  7. The Möbius Mystery Has Stumped Mathematicians for 46 ... - AOL

    www.aol.com/lifestyle/m-bius-mystery-stumped...

    The Möbius strip is one of the most famous objects in mathematics. Discovered in 1858 by two German mathematicians—August Ferdinand Möbius and Johann Benedict Listing—the Möbius strip is a ...

  8. Aromaticity - Wikipedia

    en.wikipedia.org/wiki/Aromaticity

    Möbius aromaticity occurs when a cyclic system of molecular orbitals, formed from p π atomic orbitals and populated in a closed shell by 4n (n is an integer) electrons, is given a single half-twist to correspond to a Möbius strip. A π system with 4n electrons in a flat (non-twisted) ring would be anti-aromatic, and therefore highly unstable ...

  9. Hückel - Wikipedia

    en.wikipedia.org/wiki/Hückel

    Hückel or Huckel may refer to: Erich Hückel (1896-1980), German physicist and chemist Debye–Hückel equation (named after Peter Debye and Erich Hückel), in chemistry, a method of calculating activity coefficients; Hückel method (named after Erich Hückel), a method for the determination of energies of molecular orbitals